In a computer system, the number of electronic devices such as servers, storages, and network devices increases as the scale of the system becomes larger. If the number of electronic devices increases as described above, a storage frame called rack is used to store efficiently the electronic devices and realize a small footprint. Further, if the electronic devices are to be mounted in the rack, housing-mount rails for mounting the housings of the electronic devices are laid from the front surface to the rear surface of the rack. Then, the housings of the electronic devices are placed on the housing-mount rails and the electronic devices are stacked in the rack. Such a rack is regulated in height of housings to be stored by 1 U.
Even if the electronic devices are to be mounted in the rack, it is not requested that the electronic devices are stored in the entire rack. If the electronic devices are not stored in the entire rack, there occurs an empty space at the front side of the rack where no electronic devices are mounted. When there is an open space at the front side of the rack, air exhausted from the electronic devices flows back into the electronic devices, and the electronic devices suck again the returned exhaust air. In this state, the electronic devices are not properly cooled but accumulate heat that may cause a crash of the electronic devices. Thus, blank plates are attached to the space at the front side of the rack to fill the front space.
Since there may be spaces of various sizes in the rack, blank plates for 1 U, 2 U, and 3 U are provided to support spaces of all sizes. Conventionally, it is determined a space of what U is open at the front side of the rack, and then a blank plate appropriate for filling the determined space is selected and attached. In the case of adding an electronic device, after the blank panel is removed, the housing is mounted, a blank panel suited for the remaining space is selected, and then the selected blank panel is attached. Meanwhile, removing a mounted electronic device from the rack also requests reselection and attachment of a blank plate. Thus, a plurality of blank plates are prepared at any time and a storage space is secured for the blank plates. In addition, to add or remove a housing, there arises a troublesome labor of replacement and attachment of blank plates.
To fill a space open at the front side of a rack, there has been suggested a conventional technique by which, in a rack to which a printed board is attached, two plates formed by corrugated plates or rigid plates are stacked together and placed according to the width of an empty slot to seal the rack. In addition, there has been suggested a conventional technique by which plates with convex and concave portions on both sides are joined together by fitting the convex and concave portions, thereby to adjust the width of the plates and seal the rack to which a printed board is attached.
Patent Literature 1: Japanese Laid-open Patent Publication No. 08-307079
Patent Literature 2: Japanese Laid-open Utility Model Publication No. 63-131191
However, in the case of using the conventional technique by which plates are stacked, a plurality of plates are prepare to support the space sizes of 1 U, 2 U, and 3 U. Furthermore, some blank plates are added or removed. This causes wasteful operations such as securing a storage place for spare or unused blank plates or scrapping of unused blank plates. In the case of using the method in which plates are joined together with convex and concave portions to match the plate size to the space size, a plurality of plates are prepare to support the space sizes of 1 U, 2 U, and 3 U. Furthermore, some blank plates are added or removed. Further, for formation of an appropriate space, troublesome operations are performed such as removing the blank plates, fitting the convex and concave portions, and then attaching the blank plates again.